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Genus Craesus

Caterpillar medusa - Craesus latitarsus How many sawfly larvae can fit on a leaf? - Craesus latitarsus Green Worms devouring Birch tree - Craesus latitarsus Craesus latitarsus (probably) - Craesus latitarsus Craesus sawfly larvae on gray birch - Craesus latitarsus Craesus latitarsus? - Craesus latitarsus Sawfly larvae on river birch - Craesus latitarsus
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon ("Symphyta" - Sawflies, Horntails, and Wood Wasps)
Family Tenthredinidae (Common Sawflies)
Subfamily Nematinae
Tribe Nematini
Genus Craesus
Synonyms and other taxonomic changes
=Croesus Leach 1817 (misspelling)
4 spp. in our area(1)
Comment from Dave Smith: "The large, flattened hind basitarsus is a character for the genus. Three species, all similar in color, occur in eastern U.S. They are separated by the texture of the mesopleuron and characters in the ovipositor - things I can't see in pictures. The most common is C. latitarsus Norton, the dusky birch sawfly. Other species feed on Castanea (chestnut) and Corylus (hazelnut). . . Most all emerge in the summer, July through August."